///// Any gurus / experts on 7.3 idi ? /////

[Andyinchville1]

Hi All,

I've had a 94 Ford e350 with a 7.3 IDI diesel for quite some but I never really used it much other than minor towing here and there.

Recently however , I found some work for the van and have been driving it literally 7 days a week 11 hours a day.

As a matter of fact I had gotten so busy with it I even bought a second van similar to it for only $1,300.

Anyways, I was wondering if there are as any gurus out there that also works on the 7.3 IDI ?

I'm figuring with all the diesel people out here I'm sure there are many members that run other diesels in addition to our little 1.9 tdi's.

Anyways any gurus / tdi ers out there work 7.3 idi engines also?

I did check some of the 7.3 L / Powerstroke forums but they don't really have anything similar to our gurus.

Thanks in advance for any and all help

Actually I'll reach out to the guru that works on my v w but I figured I would also cast a broader net as well.

Thanks in advance for any and all help

Andrew

 

[oilhammer]

I don't know a lot about them, but have serviced a few of them over the years. I also owned a 1990 F350 with the old IDI 7.3L (it also had a Hypermax turbo kit installed on it when it was brand new). It is a good engine, not as powerful as the later engines, but certainly able to get the job done, and amazingly not too terribly bad on fuel despite the size. My F350, slushbox and all, used the same amount of fuel as my F150, and the 150 is a 4.9L/stick regular cab, the 350 was a Supercab dually... with a 4.10 rear end to boot! It also didn't care how much I put in the bed nor how much I hooked behind it.

I know the E-vans' fuel filters are a messy pain to change, as they are right over the top of the engine.

What are you needing to do to it? They are a pretty simple engine.

 

[Andyinchville1]

HI,

The issue I am having with the Van I just bought (1993 E350) is that it smokes alot at idle and low speeds (it seems to clear up at highway speeds tho but then again it may be only be because the high speeds makes for so much air that it dissipates the smoke ?

Anyways, I am paranoid that I seem to see a bit of blue in it BUT the owner swears it doesn't burn or leak oil ( I can see that it is a very dry / no leak engine / trans ... it seems to be a different color than just black or gray buy maybe my imagination / paranoia) ...

I removed the oil cap but that did not show any blowby .... I looked for a draft tube but did not see one.

I have not driven the van long enough to see about the oil burning possibility (are there tests to see if oil is burning other than just driving it alot and seeing if the oil level gets lower?).

I was happy to see that a set of injectors (reman and pop tested) is not big $$.

It used to belong to a turkey plant and they used the van to haul baby chicks in it so I was a little worried they idled it for long periods of time during transport (the man selling it used to drive the van then bought it from the company and said they did have to keep the climate controlled when transporting the van so sometimes it did have to idle for awhile until they offloaded it (the van has about 250K miles on it but hours on engine unknown).

Other than some rust issues and the smoking the van seems good .... even good tread on the tires and the AC works so even if is continues smoking it'll be OK BUT I would prefer it NOT to smoke .

Thanks

Andrew

 

[oilhammer]

White bluish smoke is oil, but on a diesel it could also be poor combustion. Really not a good easy way to check that, though. You can do a compression test, but it could just as easily be poor injector health.

I go for the low hanging fruit first: run some diesel purge through it, change the oil and filter, and drive it for a bit and see how it does. I'd also put some fuel system cleaner in the tank for a couple tanks and see if that helps.

 

[Mozambiquer]

I've done quite a few of both the idi fords and the power strokes.
One of the common issues is the fuel filter allowing air into the lines. I don't recall if the vans had it, but there was a separate water separator that also often leaked air.

 

[Andyinchville1]

White bluish smoke is oil, but on a diesel it could also be poor combustion. Really not a good easy way to check that, though. You can do a compression test, but it could just as easily be poor injector health.

I go for the low hanging fruit first: run some diesel purge through it, change the oil and filter, and drive it for a bit and see how it does. I'd also put some fuel system cleaner in the tank for a couple tanks and see if that helps.

HI

Interesting thought about the fuel ....

I remember getting close to the exhaust pipe to have a closer look at the smoke and the smoke actually made my eyes water ... I don NOT ever recall diesel fumes doing that before ..... maybe there is something funky going on with the classic fuel in the tank...

Anyways, I took the van for a test drive and the water fuel light lit up so I opened the water drain on the filter and the light went out ..... this happened several times during my driving the van (FWIW the fuel filter looked pretty new)

When I got back after throughly warming up the van the smoke was still there but maybe to a lesser degree by a smidge ....

I told the owner about the water in fuel light and he said that water may have gotten in there because the tank was somewhat empty and the cold and warm cycles may have caused condensation in the tank ....

I have never had issues with water in the tank before so I guess there is a first for everything ... luckily it is relatively easy to drain BUT it does make a mess because the fuel drains right into the "V" of the engine.

Anyways, I had thought about draining the fuel tank hoping to get the water and old fuel out but I still had to drive home (about 70 Miles) so I decided to dillute the fuel with fresh fuek and adding a triple dose of power service gray bottle and 2 stroke oil at a rate of about 1 oz per gallon.

After the drive home it still smokes pretty much the same.

I attempted a cold after sitting a couple days in temps of about 50 degrees ....

The engine was a bit hard to start ( the wait to start light and glow plug relay clicking seemed normal) and after it fired, there was a big cloud of smoke , and a fair amount of "chugging" then a "miss" for a bit .... after about a minute or so the miss went away and the engine again ran smoothly.... still smokey but at least smoothly.

Is it possible the "miss" was a bad injector making itself known ? I suppose it could also be an air leak slowly working itself out also? How to figure that out?

Maybe running a tank or 2 through the van will help .... have to get plates for it and fix the cables in the doors so the doors open from the outside so I can put it to work and get fuel through it.

On the other hand a full set of 8 reman injectors is only about $250 to $375 and a pop tested matched set only a little more .... a bargain compared to our ALH injectors for twice as many !

On the other hand how does one know its not a weak injection pump ?

Side thought .... I will have to check the air filter also ..

I guess my plan is (unless there is a better one) run the van for a bit with heavy doses of fuel system cleaner (several tanks) , then change the oil / fuel filter .... (or maybe change the oil now since I don't know how long its been since that was done).

if that does not "fix" the issue spend the $$ for injectors and hope that fixes it ( I'll have to look into timing the engine also since I have read about that as a possibility too).

Any other ideas or is that what I should do?

Thanks

Andrew

 

[Mozambiquer]

So, I would make sure you don't have air getting into the fuel system first, there's also an orfice in the fuel return that can cause issues as well. I don't remember exactly, but I seem to recall that the fitting on top of the injector pump can get plugged and it can also cause white smoke.
The smoke burning your eyes is not surprising, it would be incomplete burn of the fuel. To diagnose, you have to go back to the basics. What does a diesel need to have a complete burn?
Compression, air, fuel and all that in the correct timing.
Low compression can cause incomplete burn, which can be verified by a compression test.
Air. Well, it needs to have a clean air filter and nothing blocking the air from getting in.
Fuel. Well that one is a bit more finniky, as not only does it need fuel, but the fuel needs to be good quality and atomized correctly.
Start with the fuel supply though, make sure there's good fuel quality (old diesel will smoke, if it even runs. I just replaced the whole fuel system on a motor home with a Cummins, because it sat for 10 years, and the fuel gummed the whole system up)
Next, it needs to not have contamination (water, air, etc) so check for air leaks in the suction side. You also need fuel flow from the lift pump and a non restricted fuel filter (they should be changed anyway)
The injection pump pressurizes the fuel to send to the injectors, if it's not pressurizing correctly, it won't atomize the fuel very well.
Then the injectors, if they're worn or sticking, or leaking, you have the same thing. Each one of those things can cause white smoke.
I'd start off with quality fuel and do a diesel purge from the bottle, change your fuel filters and check all the fuel lines back to the tank.
Make sure the fuel return line fitting on top of the injection pump is clean. If crud builds up in there, it'll also smoke white.
Let me know what you find.

 

[oilhammer]

The IDI injectors are very simple in comparison to a DI injector, that's why they are so cheap. VAG IDI injectors are relatively cheap, too.

Good news is, they are SO simple and SO crude, that you can easily SEE with the naked eye if the flat face of the injector is worn around the pintle some.

Stanadyne makes the injection pumps on those old IH engines Ford used. They are no Bosch product, and sometimes need to be refreshed, which is something either a shop that rebuilds them can check out for you or you can purchase one already rebuilt.

Water in the fuel is bad for diesel injection parts. So it is very possible the entire system is suspect. There is also a mechanical fuel pump on the engine (same as the old carburetor IH gas V8s, essentially), that is suspect to get weak and cause some issues with starving the injection pump for fuel that can cause some problems, too.